It is common to anchor various well tools such as hangers or well packers inside of a well casing by means of slips. The slips are actuated outwardly such as hydraulically or mechanically whereby the teeth on the slips bite into and engage the well conduit or casing to support the well tool from movement in one or both directions in the conduit. However, in some cases the teeth on the slips do not firmly embed themselves into the inside of the conduit. It is also difficult for the slips to engage and grip the interior surface of well conduit made of materials having hardened surfaces or constructed of high strength materials.
Therefore, the present invention is directed to providing a tubular well tool receiving conduit such as a special casing nipple or joint which includes means for positively anchoring the well tool to withstand high differential loading from either the top to bottom or from the bottom to top and for increased load-bearing strengths and/or pressure retention and having means for coacting with well tool seals to create a greater sealing area contact and creating multiple independent seal surfaces.